Abstract: A facility for manufacturing concrete and a method of operation thereof which allow for the benefits of alkali metal activated fly ash hydraulic cement to be realized, which allow the disadvantages associated therewith to be avoided, which allows widespread implementation of alkali metal activated fly ash hydraulic cement as a low-cost and environmentally-friendly substitute for Portland cement, in whole or in part, in traditional applications, and which enables new applications taking advantage of the superior characteristics of alkali metal activated fly ash cement.

Abstract: A method for continuously batch mixing a homogenized cement slurry is provided that includes providing first and second mix tubs which each perform a process which include: receiving a measured quantity of solid and liquid constituents of a cement mixture; mixing the solid and liquid constituents of the cement mixture into a homogenized cement slurry; and delivering the homogenized cement slurry into a well. In this method, the first and second mix tubs alternate these delivering processes in a synchronized manner such that one of the first and the second mix tubs continually delivering its corresponding homogenized cement slurry to a well pumping system.

Abstract: Apparatus and methods produce substantially continuous batches of high-strength concrete. Portland cement, flyash, sand, water, and concrete chemical additives are premixed in a multi-stage process, prior to final mixing with the coarse aggregates. In sequence, the complete mixing process includes: 1) a twin-shaft compulsory mixer to blend the materials, then disposing the mixture into; 2) a horizontal screw conveyor, continuously mixing as the mixture passes through the housing, thereby disposed simultaneously with the coarse aggregates into; and 3) the mixer concrete delivery truck, wherein the concrete is mixed further.

Abstract: A method of filling seabed holes involves vessels that locate the holes with sonar and one of which has onboard capabilities for storage of a solid and mixing it with liquid to create a pumpable slurry. The slurry is delivered through a coiled line that is fed out overboard and the end of the line is held in position by maintaining the vessel at the desired location during slurry pumping. The hose end can be held fixed or progressively raised during slurry delivery, depending on the starting depth. The hose further has an end feature that counteracts the tendency of the hose to whip from the force created by the pumped slurry exiting the end. The slurry encounters a plate at the hose end with lateral exits preferably equally spaced circumferentially to maintain the hose end in a steady position as the slurry is delivered.

Abstract: Methods for controlling the in-feed and discharge rates of materials flowing into and out of a mixing process where one priority is to achieve a target mixture flow rate from the mixing process and another priority can be to achieve a target value for a mixture property. Actuators can be operated to control material in-feed rates, the mixture composition, and discharge rate, and can maintain a hold-up of the mixture in the mixing process. A total flow rate controller provides a control signal to a controller acting on the discharge rate and a controller acting on the in-feed rates. The mixture discharge flow rate can be automatically reduced from its desired target when the commanded rate of at least one of the materials exceeds its available supply rate as inferred from an inability to maintain the targeted value for the mixture property.

Abstract: A wet mixer apparatus and method for its use, the mixer having a vertical mixing chamber for forming a wet slurry of a cementitious slurry and water. The vertical mixing chamber is designed to provide the required amount of mixing to provide thoroughly mixed, uniformly thin slurry within a mixing residence time that allows for adequate supply of slurry to ensure continuous operation of an associated cement panel production line. Gravity feeding for separate supply of cementitious powder and water to the slurry mixing area of the chamber without pre-mixing of the powder and water is also disclosed.

Abstract: A process employing a wet mixer having a vertical mixing chamber for forming a wet slurry of a cementitious powder and liquid. The vertical mixing chamber is designed to provide the required amount of mixing to provide thoroughly mixed, uniformly thin slurry within a mixing residence time that allows for adequate supply of slurry to ensure continuous operation of an associated cement panel production line. Gravity feed means for supply of cementitious powder and water to the slurry mixing area of the chamber is also disclosed.

Abstract: Methods of controlling a volumetric ratio of a material to total materials in a mixing vessel are provided. In various embodiments, the methods may comprise: estimating the volumetric ratio of the material to the total materials in the mixing vessel and an output flowrate of the material from the mixing vessel using a volumetric ratio observer; dynamically recomputing the commanded input flowrate of the material based on outputs of the volumetric ratio observer using a flow regulator; and adjusting an input valve of the material based on the commanded input flowrate of the material using a flow modulator. The mixing vessel may include a first mixing vessel partially separated from a second mixing vessel. In this case, a height of the total materials in the second mixing vessel may be estimated using a height observer.

Abstract: A method for continuously mixing a borehole fluid such as cement includes using a measurement of the solid fraction of a cement slurry as it is being mixed to determine the ratio of the solid and liquid components to be added to the slurry. A system for mixing the includes a liquid material (water) supply including a flow meter; a solid material (cement) supply; a mixer which receives the liquid and solid materials and includes an output for delivering materials from the mixer to a delivery system; a device for measuring the amount of material in the mixer; and a flow meter in the output; wherein measurements from the flow meters and the device for measuring the amount of material in the mixer are used to control the amount of solid and/or liquid material added to the mixer.

Abstract: A method for delivering a pre-weighed package comprising sand, aggregate and dry cement to a mixing site comprises the steps of preparing a first mixture comprising fine aggregate and coarse aggregate at an offsite plant. The first mixture is placed into a first storage compartment of a hopper and the load of dry cement is placed into a second storage compartment of the hopper. The hopper is transported to the mixing site, where the first mixture and the cement are discharged from the hopper and mixed to form a concrete slurry. The hopper comprises the first storage compartment and the second storage compartment, where there is a water tight divider separating the first storage compartment and the second storage compartment. The storage compartments have respective inlets and outlets for receiving and discharging the respective components.

Abstract: A method for continuously mixing a borehole fluid such as cement includes using a measurement of the solid fraction of a cement slurry as it is being mixed to determine the ratio of the solid and liquid components to be added to the slurry. A system for mixing the includes a liquid material (water) supply including a flow meter; a solid material (cement) supply; a mixer which receives the liquid and solid materials and includes an output for delivering materials from the mixer to a delivery system; a device for measuring the amount of material in the mixer, and a flow meter in the output; wherein measurements from the flow meters and the device for measuring the amount of material in the mixer are used to control the amount of solid and/or liquid material added to the mixer.

Abstract: A computer controlled pumping and measuring system is used to dispense chemicals into a concrete mix. The redundant use of positive displacement pumps and flow meters ensure that any problems with the chemical dispensing are immediately caught. The computerized control system may be operable to control exact batch configurations of concrete and aggregate in conjunction with the chemical dispensing, as well as provide precise mixture control and recording of the various components.

Abstract: A method for dosing reinforcing fibers in a mixing silo during the manufacture of fiber concrete. The reinforcing fibers as supplied in a chain packing of sacks. The sacks may be made of material which can be disintegrated in mortar or concrete. The chain packing including sacks filled with reinforcing fibers for carrying out the method may be made of material which can be disintegrated in mortar or concrete.

Abstract: A process and equipment for producing multi-color concrete products, including architectural concrete blocks, concrete bricks, modular concrete products that are suitable for use in landscaping applications, such as retaining wall blocks, concrete pavers, and concrete slabs. The invention includes a hopper that is divided into separate sections, with each section intended to contain a differently colored concrete. Each hopper section includes a controllable discharge opening that permits precise control of the amount of each concrete color that is discharged from the hopper. The colored concrete is then transported to and dumped into a hopper of a concrete product production machine, where the concrete is blended into a multi-color concrete blend for use in producing the concrete products.

Abstract: A method of producing, in a continuous plant, a bituminous conglomerate containing aggregates and at least bitumen comprises the steps of drying the aggregates and mixing them with a measured amount of at least the incoming bitumen to form the bituminous conglomerate; weighing the obtained bituminous conglomerate; calculating the amount of dry aggregates present in the conglomerate as the difference between the detected weight of the obtained bituminous conglomerate and the measured amount of at least bitumen; and adjusting in real time the amount of at least the incoming bitumen depending on the calculated amount of dry aggregates, so as to keep this bitumen amount within preestablished proportions with respect to the calculated amount of dry aggregates.

Abstract: A ready mix batch hauler system for efficiently transporting concrete mixing materials to a job site. A batch hauler truck is provided having a storage tank pivotally attached to the frame of the batch hauler truck. The storage tank has a first reservoir for holding particulate material and a second reservoir for holding cement. The user positions the batch hauler truck such that the rear discharge of the storage tank is positioned near the front discharge of a front end discharge truck mixer and elevates the storage tank. A first auger draws the cement into the second reservoir through an opening and a second auger draws the mixture of the cement and particulate material through the rear discharge. An alignment structure is preferably utilized for aligning the batch hauler truck with the front end discharge truck mixer.

Abstract: A method for continuously mixing a borehole fluid such as cement includes using a measurement of the solid fraction of a cement slurry as it is being mixed to determine the ratio of the solid and liquid components to be added to the slurry. A system for mixing the slurry includes a liquid material (water) supply including a flow meter; a solid material (cement) supply; a mixer which receives the liquid and solid materials and includes an output for delivering materials from the mixer to a delivery system; a device for measuring the amount of material in the mixer; and a flow meter in the output; wherein measurements from the flow meters and the device for measuring the amount of material in the mixer are provided to a control system which provides control signals to automatically control the amount of solid and/or liquid material added to the mixer.

Abstract: A volumetric solid and liquid dispenser includes a drum sized for receiving and containing a predetermined volume of solid material from a solid material supply source. The supply source can be a hopper positioned above the drum. The drum is rotatably mounted to a support frame and can be rotated from a position in which it receives solid material from the supply source to a dispensing position in which it dispenses the solid material into a receptacle below. A liquid metering and dispensing container dispenses a predetermined volume of liquid into the receptacle for mixing with the solid material. The invention is particularly useful for dispensing predetermined volumes of sand and water into a cement mixer for mixing with mortar.

Abstract: A method and apparatus for efficiently forming individual building units is provided, generally includes providing a plurality of molds, each capable of simultaneously forming a plurality of building units. Batches of cementitious slurry are individually mixed in order to control the density of each building unit formed. The ingredients are individually measured and combined into the mixing device. The cementitious slurry is then conveyed or transported and poured into one of the molds. The method provides the ability to control the amount of cementitious slurry in each batch in order to control to the extent possible the quantity of cementitious slurry poured into each mold and the ability to precisely control the dimensions of each building unit produced.

Abstract: Producing both colored and noncolored lightweight aggregates. The processes involve mixing a lightweight fine material such as ash with cement, and optionally pigment, then agglomerating the mixture, curing, and sizing the lightweight aggregate. Calcium stearate is added to the lightweight aggregate for reducing the moisture permeability of the lightweight aggregate end product. The colored and noncolored lightweight aggregate may be used in a variety of ways such as to provide a lightweight concrete mix with the same exterior and interior color, and for other asphalt pavement, geotechnical, horticulture, and specialty uses.

Abstract: A filter vent system and method for separating entrained airborne particulate matter from the conveying fluid is disclosed, particularly as it relates to filling a storage vessel. The filter system employs a simplified, yet more efficient filter cleaning arrangement, in which the entire clean air plenum on the downstream side of a filter array of one or more filter units is periodically pulsed with a large burst or pulse of relatively high pressure air from a single source which rapidly raises the plenum pressure to, in turn, produce a temporary pulsed flow reversal in the filter units which blasts through the filter pores to displace particulate matter collected on the upstream side of all of the filter units alike thereby cleaning or re-generating the filter surfaces.

Abstract: A system and method of forming a mixture from two elements according to which the elements are introduced into a vessel and mixed in the vessel before being discharged from the vessel. The flow rate of one of the elements is controlled to maintain a constant level of the mixture in the vessel and the flow rate of the other element is controlled to maintain a predetermined ratio of the flow rate of the latter element and the discharge flow rate.

Abstract: Given green sand is obtained by a mixing operation that is carried out for a short period of time. Discarded sand is supplied as supplementary sand to a sand processing line, so that molding sand can be recycled. Green sand for a molding is used for facing sand or the pocket sand. Bentonite-covered sand is made by mixing reproduced sand, new sand, and discarded sand or any or all of them. The bentonite-covered sand is added to collected sand to supplement it. Also, the bentonite-covered sand is mixed with water, and used for facing sand or the pocket sand.

Abstract: An apparatus (25) for transporting pre-measured quantities of fibers in a plurality of containers (13), separated by a plurality of webs (14), joining the containers together at spaced intervals, to a mixer (22) for cementitious materials, the apparatus comprising a conveying assembly (26), the containers therethrough; a counter assembly (28); a web slitting assembly (29); and a process controller (30), which activates the web slitting assembly in response to input from the counter assembly, in order to sever a determined number of the containers from the webs for conveyance into the mixer. A method for conveying pre-measured quantities of fibers suitable for the reinforcement of cementitious materials to a mixing apparatus is also provided as well as a train for providing pre-measured quantities of fiber comprising a plurality of containers containing the fibers; and a plurality of webs, joining the containers together at spaced intervals.

Abstract: A method and apparatus for performing multiple ratio analysis of aggregate particles, wherein the method includes the steps of measuring a first maximum dimension of a particle, measuring a second maximum dimension of a particle in a direction substantially perpendicular to the first maximum dimension, and inputting the first maximum dimension and second maximum dimension into a computer having a processor. Using the computer, a particle ratio of the first maximum dimension to the second maximum dimension for the measured particle is computed and the particle ratio is classified into one of a predetermined plurality of different ratio ranges, each of these plurality of different ratios representative of a different range of particle shapes.

Abstract: A portable concrete plant for producing ready mix concrete proximate to a location where the ready mix concrete is used. The portable concrete plant includes storage regions for storing components used in the ready mix concrete. The portable concrete plant also includes a slurry mixer for preparing slurry that is used in the ready mix concrete. The portable concrete plant further includes conveying systems for conveying the components from the storage regions and from the slurry mixer to a system discharge port.

Abstract: The present invention to provides for a novel asphalt mixing plant which is portable, that is, capable of being transported from one site to another. The portable asphalt mixing plant has a control system that adjusts the rate at which crumb rubber is added to oil so as to maintain a constant oil/rubber ratio in a mixer. The blending control process has a CPU to control the rate at which asphalt is pumped into a mixer and the rate at which crumb rubber is fed to the same mixer so as to maintain a constant asphalt rubber ratio in the produced asphalt.

Abstract: A method for continuously mixing a borehole fluid such as cement includes using a measurement of the solid fraction of a cement slurry as it is being mixed to determine the ratio of the solid and liquid components to be added to the slurry. A system for mixing the includes a liquid material (water) supply including a flow meter; a solid material (cement) supply; a mixer which receives the liquid and solid materials and includes an output for delivering materials from the mixer to a delivery system; a device for measuring the amount of material in the mixer; and a flow meter in the output; wherein measurements from the flow meters and the device for measuring the amount of material in the mixer are used to control the amount of solid and/or liquid material added to the mixer.

Abstract: Given green sand is obtained by a mixing operation that is carried out for a short period of time. Discarded sand is supplied as supplementary sand to a sand processing line, so that molding sand can be recycled. Green sand for a molding is used for facing sand or the pocket sand. Bentonite-covered sand is made by mixing reproduced sand, new sand, and discarded sand or any or all of them. The bentonite-covered sand is added to collected sand to supplement it. Also, the bentonite-covered sand is mixed with water, and used for facing sand or the pocket sand.

Abstract: A dual conveyor apparatus transports two cement-making materials in opposite directions. The two conveyors share a common channel so that the materials intermix during transport. The conveyors a driven by a motor, one conveyor rotating in a first direction and the other conveyor rotating in the opposite direction. Each conveyor extends upwardly at an incline from its feed end to its discharge end. The rotation of each conveyor can be altered to vary both the blend and the throughput of the device.

Abstract: The invention relates to a method and a device for providing at construction sites paste-like building materials, especially mortar, being delivered in a fixedly pre-determined basic consistency. A conveying and mixing pump with an additional water supply opening is provided below the storage container for the paste-like building material. By means of the water supply opening, additional water is mixed with the mortar in order to produce the desired mortar consistency. For this purpose, a mixing portion having hedgehog-type mixing elements is provided.

Abstract: A method for continuously mixing a borehole fluid such as cement includes using a measurement of the solid fraction of a cement slurry as it is being mixed to determine the ratio of the solid and liquid components to be added to the slurry. A system for mixing the includes a liquid material (water) supply including a flow meter; a solid material (cement) supply; a mixer which receives the liquid and solid materials and includes an output for delivering materials from the mixer to a delivery system; a device for measuring the amount of material in the mixer; and a flow meter in the output; wherein measurements from the flow meters and the device for measuring the amount of material in the mixer are used to control the amount of solid and/or liquid material added to the mixer.

Abstract: A method for selecting proportions of aggregate for incorporation into concrete comprises several steps. First, a maximum aggregate size for a specific application is determined. A sample of the maximum size aggregate is loose poured into a container. The percentage voids in that sample is then calculated. An amount of smaller sized aggregate equal to approximately the volume of percentage voids calculated earlier is added to the sample until a reduced volume of voids in the mixed sample is achieved. Finally, the amounts of aggregate determined to have the reduced volume of voids in the mixed sample are used in a concrete mixture.

Abstract: A system for developing a concrete mix design that allows a user to input a set of initial design parameters (such as required average compressive strength) for the design, and to specify various design criteria (such as the cementitious materials, aggregates, and admixtures to be used in the design) using a series of input screens. The system then displays several key initial design parameters and design criteria within a design criteria and parameters summary that is displayed on a single “worksheet screen.” One or more of these criteria and/or parameters is displayed in user-modifiable format. Upon pressing a “calculate” button, the system displays an initial set of design specifications that meet the specified design parameters and criteria. The user may then modify any of the user-modifiable design parameters and criteria. In response such modifications, the system immediately generates an updated set of specifications that satisfies the revised criteria.

Abstract: Mixing machine for mixing cement components with water to provide a pumpable slurry, and a method for its use. The machine includes a mixing vessel having an inlet for water at an average flow rate and for dry cement components, and a water tank for supplying water at a high flow rate to the mixing vessel and having an internal diaphragm separating the tank into water and air compartments. The water tank includes an inlet for admitting water to the water compartment and a conduit communicating the water compartment with the mixing vessel and capable of accommodating the flow of water at an average flow rate substantially greater than the average flow rate of water into the water compartment. The conduit includes a water meter and valve to monitor and regulate, respectively, the quantity of water supplied to the mixing vessel.

Abstract: A portable concrete plant for producing ready mix concrete proximate to a location where the ready mix concrete is used. The portable concrete plant includes storage regions for storing components used in the ready mix concrete. The portable concrete plant also includes a slurry mixer for preparing slurry that is used in the ready mix concrete. The portable concrete plant further includes conveying systems for conveying the components from the storage regions and from the slurry mixer to a system discharge port.

Abstract: The invention relates to a method and a device for providing at construction sites paste-like building materials, especially mortar, being delivered in a fixedly pre-determined basic consistency. A conveying and mixing pump with an additional water supply opening is provided below the storage container for the paste-like building material. By means of the water supply opening, additional water is mixed with the mortar in order to produce the desired mortar consistency. For this purpose, a mixing portion having hedgehog-type mixing elements is provided.

Abstract: A mobile system and process for manufacturing cement additives and/or concrete admixture products comprises at least two tanks each containing a different raw material for manufacturing cement additives or concrete admixtures; a frame for mounting and transporting as an integral unit at least two pumps operative to transfer the raw materials into a blender which mixes the raw materials together to provide a cement additive or concrete admixture for dispensing at the destination site, which could be the manufacturer's new or remote manufacturing site, or even a customer's site such as a cement plant or a ready-mix concrete plant. The frame can be placed upon or attached to wheels, as in a truck or trailer frame, and the tanks may also be placed on or secured to the truck or trailer frame. A preferred skid-mounted system comprises pumps, valves, meters, and a computer processor unit which can control the equipment and permit adjustments to be made at the destination site.

Abstract: A method of manufacturing concrete with a fiber additive and other ingredients including the steps of mechanically manipulating a shipping container (36) having a gross amount of fiber additive (50) substantially greater than the an amount susceptible to unaided manual handling with a mechanical manipulator to dump the gross amount of fiber additive (50) from the shipping container (36) into an additive hopper (46) moving at least some of the fiber additive (50) dumped in the additive hopper (46) to an additive hopper-bin (20) by means of a mechanically powered fiber conveyor (48) and conveying a preselected amount of the fiber additive (50) from the additive hopper-bin (20) to a mixer (14) for mixing with the other ingredients of the concrete being made.

Abstract: A system and method for providing raw mix proportioning control in a cement plant. A raw mix proportioning controller determines the correct mix and composition of raw materials to be transported to a mixer. The raw mix proportioning controller uses an inverse controller to determine the proper mix and composition of raw materials. The inverse controller takes targeted set points and the chemical composition of the raw material as inputs and generates the proportions of the raw material to be provided as an output for the next time step. The output is generated by using a geometric interpretation of the control process and a non-linear constrained optimization.

Abstract: A system and method for providing raw mix proportioning control in a cement plant with a gradient-based predictive controller. A raw mix proportioning controller determines the correct mix and composition of raw materials to be transported to a mixer. The raw mix proportioning controller uses a gradient-based predictive controller to determine the proper mix and composition of raw materials. The gradient-based predictive controller takes targeted set points and the chemical composition of the raw material as inputs and generates the proportions of the raw material to be provided as an output for the next time step. The output is generated by using a non-linear constrained optimization.

Abstract: A system and method for providing raw mix proportioning control in a cement plant with a fuzzy logic supervisory controller. A raw mix proportioning controller determines the correct mix and composition of raw materials to be transported to a mixer. The raw mix proportioning controller uses the fuzzy logic supervisory controller to determine the proper mix and composition of raw materials. The fuzzy logic supervisory controller takes targeted set points and the chemical composition of the raw material as inputs and generates the proportions of the raw material to be provided as an output for the next time step.

Abstract: An admixture dispensing and concrete mixer monitoring system which determines the correct amount of admixture, such as a stabilizer, to dispense in a load of unused concrete or for washing out a concrete mixer includes an admixture dispensing unit linked to a computer system. The computer system includes a processor which controls and monitors the operation of the dispensing unit which includes an admixture piping system and a water piping system. The processor is linked to various pumps, meters and valves in the admixture and water piping systems to control the flow of admixture and water into the concrete mixer. Additionally, the computer system provides questions and prompts to the user to assist in accurately and quickly determining the correct amount of admixture to deposit in the concrete mixer. The computer system also allows the tracking of multiple delivery or mixing trucks and their content status at multiple mixing plants to assist in the scheduling thereof.

Abstract: A portable chassis-mounted continuous flow, blending and mixing plant utilizing a Programmable Logic Controller and belt scales to continuously meter and adjust the flow of aggregate as well as maintain the proper ratio and flow of additives, both dry and liquid.

Abstract: A method and a system for controlling the mixing of raw materials for cement. Component contents of a sample material is obtained at an exit side of a mill system to obtain measured modulus values of hydraulic modulus HM, silica modulus SM, and iron modulus IM of a raw material mixture. Estimated modulus values of the component contents is determined and based on current takeout amounts of the raw materials, a mill system passage characteristic model, a component analyzer passage characteristic model, and preset component contents of the raw materials. Modulus deviation values are calculated based on differences between the estimated modulus values and the measured modulus values, and is passed through a noise removal filter. Future modulus values of the component contents are then calculated based on the raw material takeout amounts, and the preset raw material component contents. To determine predicted modulus values for calculation of updated takeout amounts.

Abstract: The described process utilizes the ash from a trash-to-steam plant and a cementitous binder along with the hot output of an earth purification process and a strictly defined quantity of water in calculated amounts to produce an aggregate which satisfies leach and strength tests and qualifies for use in road building and as a landfill cover.

Abstract: A mobile system and process for manufacturing and delivering concrete admixture finished products comprises: providing in separate transport tanks mounted on a vehicular frame at least two raw admixture materials (components); and blending together said at least two concrete admixture raw materials to provide a finished admixture product, whereby a finished admixture product is provided at a customer site, such as at a customer's mixing plant. Preferred processes and systems of the invention employ pump means for feeding admixture raw materials from the transport tanks to a blender, metering means for measuring the amount or rate of raw materials fed into the blender, and quality control units for monitoring physical characteristics of the finished product being delivered.

Abstract: A mixing device (1) having at least two concentric tubular elements (2, 3) including an outer tubular element (2) and an inner tubular element (3) inside the outer tubular element, the outer tubular element and the inner tubular element each supplying a liquid (5) or solid products to be mixed together, and a helical member (4) disposed for rotational movement inside the outer tubular element for entrainment of the liquid (5) or solid products, the helical member surrounding the inner tubular element, the outer tubular element including at least one inlet orifice (6a) for introducing the liquid (5) or solid products into the outer tubular element to be entrained by the helical member, and an outlet orifice (7) for delivering a mixture (9) of the liquid and solid products (5, 8) outside the outer tubular element, the inner tubular element (3) having an open end terminating inside the outer tubular element (2) downstream of the inlet orifice (6a) and upstream of the outlet orifice (7), wherein the mixture (9) i

Abstract: An apparatus for high capacity production of high-fluidity, colloidally mixed cement slurry. Water and cement dust are combined at metered rates by a premixing assembly which discharges into a mixing tub. The high-speed, high-shear pump recirculates the material through the tub to produce the colloidally-mixed slurry. The high-fluidity slurry may be provided to a second pump, preferably of the positive-displacement, progressive-cavity, rotor-stator type, for supplying the slurry at a metered rate. Finished foam material may also be provided to the slurry metering pump at the metered rate, so the materials are mixed to form a foamed cement grout in which the weight and quality of the material is precisely adjustable.

Abstract: A method and apparatus for mixing concrete in a concrete delivery mixing truck is provided which can yield a mix with an approximate required slump. This is achieved by monitoring the torque loading on hydraulic drive which rotates a mixing barrel and noting an anticipated minimum torque loading which, in turn, approximates to a required slump value. Liquid component is added to a mix until this minimum torque loading is noted. A CPU (17) is used to process information derived from a hydraulic pressure sensor (15) connected in the hydraulic drive motor used to rotate the mixing barrel. A volume/mass input sensor (21) can be used for meaning the amount of particulate ingredients, and a water volume sensor (25) can be used to measure the volume of liquid component added to the mix. When a known maximum volume of liquid component is added a computer can operate to prevent further liquid being added, unless it is purposely overridden.